Old cemeteries on Mulberry Island (now Fort Eustis, NPN)

Very interesting page I found about the old cemeteries of Mulberry Island, now known as Fort Eustis. The most interesting thing I saw on here, was that when the US Govt bought the property in 1918, they gave the families 30 days to remove the dead and relocate them. For some that did not comply, the graves, tombstones and all, were dug up and used in a fill by the river, their previous burial spot covered over with concrete. How is this humane? I really don’t understand.